Atomic Cu Sites Engineering Enables Efficient CO Electroreduction to Methane with High CH/CH Ratio

Electrochemical reduction of CO into high-value hydrocarbons and alcohols by using Cu-based catalysts is a promising and attractive technology for CO capture and utilization, resulting from their high catalytic activity and selectivity. The mobility and accessibility of active sites in Cu-based catalysts significantly hinder the development of efficient Cu-based catalysts for CO electrochemical reduction reaction (CORR). Herein, a facile and effective strategy is developed to engineer accessible and structural stable Cu sites by incorporating single atomic Cu into the nitrogen cavities of the host graphitic carbon nitride (g-CN) as the active sites for CO-to-CH conversion in CORR. By regulating the coordination and density of Cu sites in g-CN, an optimal catalyst corresponding to a one Cu atom in one nitrogen cavity reaches the highest CH Faraday efficiency of 49.04% and produces the products with a high CH/CH ratio over 9. This work provides the first experimental study on g-CN-supported single Cu atom catalyst for efficient CH production from CORR and suggests a principle in designing highly stable and selective high-efficiency Cu-based catalysts for CORR by engineering Cu active sites in 2D materials with porous crystal structures.[Figure not available: see fulltext.].